Very interesting discussion in this thread. I have bounced () around on spring rates a fair bit and have just pulled the 450 fronts and 250 rears out of the back of my car as they were bottoming out at Mosport going into 5A and in the second part of 2. I have to admit that the softer rear spring planted the rear tires under acceleration. As well almost every hard corner that I had the car in and was photographed, the car was tricycling. I run the car fairly low at about 2" lower in the front and 1" in the rear. I am also running a bit more power with a bridge ported 4 port S5 rotating assembly 13B with a 4 port ITB setup. The car pulls hard to 10,000 rpm. I am also running on Toyo RA1's.

I have gone back to my 550 front and 400 rear setup with no rear bar. I wonder if the differences I am seeing are due to me racing at Mosport with an average lap speed of just over 90 mph and the fact that I am running a fairly big and high rear wing, plus an AWR E Prod nose on the car, combined with the extra power. I am running a 3 Hour enduro this weekend with the stiffer setup and I will see what happens.

Very interesting thread that gives me lots to think about.

Eric